Syrian government forces seized full control of the last major town in Homs province held by Islamic State, Syrian state media reported on Saturday, as the army and its allies press a multi-pronged advance into eastern areas held by the militant group

Syrian state media cited a military source saying Islamic State militants had been killed and their weapons destroyed at the town of al-Sukhna, about 50 km northeast of the ancient city of Palmyra.

The town is also some 50 km from the provincial boundary of Deir Ezzor province, Islamic State's last major foothold in Syria and a major target for the Syrian government.

The militants have lost swaths of Syrian territory to separate campaigns being waged by government forces backed by Russia and Iran, and by the US-backed Syrian Democratic (SDF) Forces, which is dominated by the Kurdish YPG militia. The SDF is currently focused on capturing Raqqa city from Islamic State.

Thousands of opposition fighters and their families have left a number of areas in western Syria in recent months in what the government calls reconciliation deals. Syrian President Bashar al-Assad's government now controls the country's main urban centres.

The opposition and the United Nations have criticised the deals as forced displacement of Assad's enemies, often after months or years of siege and bombardment.

Syrian government forces advancing from the west have recently crossed into Deir Ezzor province from southern areas of Raqqa province.

Islamic State controls nearly all of Deir Ezzor province, which is bordered to the east by Iraq. The Syrian government still controls a pocket of territory in Deir Ezzor city, and a nearby military base.

The Syrian conflict, now in its seventh year, has killed hundreds of thousands of people and displaced more than 11 million.

On Friday an explosion hit a rebel gathering near the Syria-Jordan border in the south of Syria, killing at least 23 fighters and wounding dozens more, a war monitor and activists said.

The Syrian Observatory for Human Rights said an explosion targeted an army camp of the Syrian rebel group Jaish al-Islam near the border crossing town of Nassib.

The UK-based war monitor said the explosion was caused by a suicide bomber and the death toll was expected to rise.

A video passed to Reuters by an activist in the area claimed to show at least a dozen seriously injured people lying on a carpeted floor. Reuters could not independently verify the content of the video.

No group has claimed responsibility for the attack, but Jaish al-Islam supporters on twitter blamed the Islamic State group for the blast.